In the video (embedded below) the HoloLens headset, which allows visuals to overlap and interact with the real world, lets the user create portals that attach to walls, ceilings and other flat surfaces and then use a companion cube to test them out.

That companion cube reacts with the real world, toppling into and out of portals, onto table, slamming into walls and in one instance knocking over a virtual sentry turret from the game.

At one point in the video, the cube is sent through a portal, appearing out of the other at the top of some stairs before falling down them and into the first portal again. Players can't use the portals themselves as, we imagine, the sensation would be vomit-inducingly disorientating.

Sadly, given this is just a side-project for Wang and Valve itself is not involved, it's unlikely to ever become an actual game. However, it may catch Valve's attention and inspire whatever it is they're working on for the HTC Vive virtual reality headset.

Valve has brought the Portal universe to virtual reality in The Lab, which didn't feature portals but did take place in the same Aperture Science laboratories, and featured characters GLaDOS and Portal 2 co-op stars Atlas and P-body.

Wang has worked with a recognised IP before, creating a Pokémon AR project last year that looked just as impressive. Whatever the developer ends up working on full time in augmented reality, we'll be interested to see what he comes up with.